SIRONA Trial Heart Failure NYHA Class III

Inclusion Criteria: 1. Subject has given written informed consent 2. Male or female, at least 18 years of age 3. Diagnosis of HF ≥ 3 months with either preserved or reduced left ventricular ejection fraction (LVEF) 4. Diagnosis of NYHA Class III HF at the time of Screening with at least 1 HF-related hospitalization, HF treatment in a hospital day-care setting, or urgent outpatient clinic HF visit within the last year 5. Subjects must be receiving appropriate medical management of HF for 3 months prior to Screening and clinically stable for at least 1 month prior to study entry 6. Subjects with a Body Mass Index (BMI) \< 35 kg/mL2 and chest circumference \< 1050 mm 7. Subjects with right pulmonary artery branch diameter sized between 14 mm and 20 mm (target Sensor implant site) over a length of at least 30mm 8. Subjects with distance between target implant site (right PA branch) and ventral thoracic skin surface of \< 12cm 9. Subjects who are physically able to hold the myCordella™ Patient Reader unit (approximate weight 600g) against the ventral thoracic surface for up to 2 minutes per day while in a seated. position, as well as dock and undock the myCordella™ Patient Reader 10. Subjects with sufficient eyesight, hearing, and mental capacity to respond to the myCordella™ Patient Reader's audio/visual cues and operate the myCordella™ Patient Reader. 11. Subject has sufficient Cellular and/ or Wi- Fi Internet coverage at home 12. Subject agrees to return to the treating Investigator for all scheduled follow up visits and can return to the hospital for follow up 13. Subject compliance as defined by data collection and transmissions at least 5 days a week (does not have to be consecutive days) using the myCordella™ Hub \& Peripherals for at least 1 week during the screening period Exclusion Criteria: 1. Subjects with primary pulmonary hypertension. 2. Subjects with an active infection at the Sensor Implant Visit 3. Subjects with history of recurrent (\> 1) pulmonary embolism or deep vein thrombosis 4. Subjects who have had a major cardiovascular event (e.g., myocardial infarction, stroke) within 2 months of the Screening Visit 5. Subjects whereby RHC or computed tomography pulmonary angiography (CTPA) is contraindicated 6. Subjects with a Cardiac Resynchronization Device (CRT), Internal Cardiac Defibrillator (ICD) or pacemaker (if implanted less than 6 months or has more than a single lead), or Left Ventricular Assist Device (LVAD) 7. Any major surgery within 30 days of the Sensor Implant Visit. 8. Subjects with a Glomerular Filtration Rate (GFR) \<30 ml/min or who are on chronic renal dialysis 9. Specific liver enzymes \[Aspartate Aminotransferase (AST) (SGOT), and Alanine Aminotransferase (ALT) (SGPT) \>3 times the upper limit of normal 10. Subjects likely to undergo lung and/ or heart transplantation within 24 months of the Screening Visit. 11. Subjects with congenital heart disease or mechanical/tissue right heart valve(s) 12. Subjects with known coagulation disorders 13. Subjects with a hypersensitivity or allergy to platelet aggregation inhibitors including aspirin, clopidogrel, prasugrel, and ticagrelor; or patients unable to take dual antiplatelet or anticoagulants for one month post implant 14. Subjects enrolled in another investigational trial. 15. Known history of life threatening allergy to contrast dye. 16. Subjects who are unwilling or deemed by the Investigator to be unwilling to comply with the study protocol, or subjects with a history of non-compliance 17. Subjects with large metal implants/prostheses or any other materials in the thoracic cavity that may interfere with the Cordella™ Pulmonary Artery Sensor System performance 18. Subjects with an indwelling inferior vena cava (IVC) filter 19. Subjects who are pregnant or breastfeeding 20. Subjects whose clinical condition, in the opinion of the Investigator, makes them an unsuitable candidate for the study 21. Severe illness, other than heart disease, which would limit survival to \<1 year 22. Subjects who have had intractable arrhythmias within 2 month of the Screening Visit 23. Subjects with patent foramen ovale (PFO)